<div class="categories">
    <ul>
        <h3>Hãng sản xuất</h3>
        <?php foreach ($aryMaker as $key => $maker) { ?>
            <li>
                <a class="<?php if (isset($maker_name)) echo ($maker_name == $maker['product_maker_name_filter']) ? 'active' : ''; ?>"  href="<?php
                   echo $this->url('product/product-by-category', array(
                       'cat_id' => $category_id,
                       'cat_name' => $category_filter,
                       'order' => $order_by,
                       'maker_name' => $maker['product_maker_name_filter']
                   ));
                   ?>">
                    <?php echo $maker['product_maker_name']; ?>
                </a>
            </li>
        <?php } ?>
    </ul>
</div>